FAMILY TROGLODYTIDAE 



97 



coverts; central area very faintly lined with the paler markings, or plain 

 black; above reddish brown; side of head dull black; a narrow white 

 line over loral area and eye. 



Immature, mandible yellow; side of head faintly dusky; light line 

 over eye indistinct; foreneck grayish white to gray; rest of undersur- 

 face grayish brown to brown, with cross bars faintly indicated or 

 absent. 



These are among the more common wrens of forested regions in low- 

 land areas, found usually in heavy cover in the denser stands of wood- 

 land. Two subspecies are recognized in the Republic. The species 

 ranges from southwestern Costa Rica to Colombia, the nominate race 

 being described from central Colombia. 



THRYOTHORUS FASCIATOVENTRIS MELANOGASTER Sharpe 



Thryothorus melanogaster Sharpe, Cat. Birds Brit. Mus., vol. 6, "1881" (1882), 

 p. 230, pi. 14, fig. 2. (Bugaba, Chiriqtri, Panama.) 



Characters. — Slightly darker, more chestnut-brown on upper sur- 

 face, and on feathered area of tibia; undersurface with black of breast 

 more extensive; averaging slightly larger. 



An adult male, taken at Puerto Armuelles, Chiriqui, February 1, 

 1966, had the iris reddish brown; maxilla black; mandible dark bluish 

 gray; inner side of tarsus and sides of toes and claws dull neutral gray; 

 cuter side and front of tarsus, and tops of the toes dull black. 



Measurements. — Males (10 from Panama and Costa Rica), wing 

 65.6-69.6 (66.1), tail 53.2-58.3 (56.7), culmen from base 20.5-23.8 

 (22.2), tarsus 23.1-26.2 (24.5) mm. 



Females (9 from Panama and Costa Rica), wing 61.5-66.0 (63.9), 

 tail 50.5-55.2 (52.7), culmen from base 19.0-21.9 (20.0, average of 8), 

 tarsus 22.5-24.9 (23.5) mm. 



Resident. Found locally in forested areas (not abundant) in the 

 lowlands of western Chiriqui; recorded from west of David near 

 Divala, and Bugaba, below Concepcion south to Aguacaton, the upper 

 Rio San Bartolo and Puerto Armuelles; locally lower on the peninsula 

 to Punta Balsa, near Punta Burica. 



As these wrens are primarily inhabitants of thickets in the denser 

 cover of forests, they must now be reduced considerably in number 

 owing to the extensive clearing in the area from which they are known. 

 This western race was known early through specimens collected by 

 Arce, mainly in the Bugaba area (recorded by Salvin, Proc. Zool. Soc. 

 London, 1870, pp. 180-181). In the British Museum (Natural His- 



